This invention is directed generally to the field of contact lens disinfecting systems and more particularly to a novel and improved modular contact lens disinfecting system including a novel combination lens case and heater module and a novel combination energizing-and-timer module.
In recent years, soft and extended wear type of contact lenses have been developed as an alternative to the hard contact lenses. These soft and extended wear contact lenses are manufactured of a hydrophilic plastic porous material which can be formed to the desired lens curvature, and thereafter will absorb water and become relatively soft and pliable.
While hard contact lenses require periodic cleaning and disinfecting, the disinfecting of the soft and extended wear contact lenses is recommended more frequently. In this regard, the disinfecting of the soft lenses is recommended on a daily basis, whereas extended wear lenses as the name denotes, may be worn for a more extended period of several days, but should likewise be disinfected intermediate such periods of wear. This need for disinfecting is largely due to the porous nature of the plastic materials utilized in the construction of these newer types of lenses. Such porous material receives bodily fluids during wear which may have a number of materials dissolved therein. These dissolved materials may precipitate out and build up over time in the pores and this results in a clouding of the lens. Thorough cleaning is therefore necessary from time to time to remove this material from the pores. Moreover, such pores provide areas for bacterial growth and hence the lenses must be disinfected periodically.
Several disinfecting methods have been developed and employed with success in conjunction with soft and extended wear lenses. One such method involves placing the lenses in a saline or other disinfecting solution and thereafter heating the solution to a temperature sufficient to destroy any bacteria which may be present. A second method utilizes a chemical process to destroy the bacteria.
The thermal or heat disinfecting methods may employ either a "wet heat" process or a "dry heat" process. In the former process, the lenses are placed in a case containing a quantity of disinfecting or saline solution and the case is then placed in a second vessel containing a quantity of water which is brought to a boil, with heat being transferred to the lenses and solution in the case by way of the surrounding water. On the other hand, in the latter dry heat method of sterilization, the lenses are placed in the lens case with a quantity of disinfecting solution; however, the case is then placed in surface-to-surface contact with a heater unit. Hence, direct application of heat is obtained from the heater unit to the lens case and thence to the solution contained therein.
The present invention pertains to a disinfecting unit and system adapted for use in the "dry heat" type of process. In this regard, the present invention advantageously provides a novel modular disinfecting system design which utilizes a pair of relatively compact and easy to use modules. The first module comprises a combined case-and-heater unit module and may be utilized as a carrying case for the lenses intermediate periods of wear and/or disinfecting operations. The second unit comprises a combined energizing-and-timer unit which may be coupled with a conventional electrical outlet to receive electrical current. The two modules include mating sets of contacts for delivering energizing current from the energizing-and-timer module to the heater portion of the case and heater unit; and the timer portion of the energizing-and-timer module controls the amount of time during which this current is supplied thereby.